Cut the strawberries into slices, you can also cut them in quarters or halves.
Place the strawberries in a large glass jar, that has a tight lid, and pour the tequila over the strawberries.
Close the jar and let the strawberries infuse the tequila for about 3 days. You can check the taste on day 2 and see if it needs more time.
Once the tequila has the desired strawberry flavor, strain and remove the strawberries (discard them). Pour the tequila into an empty glass bottle and use as in cocktails or for sipping/shots.
Notes
If tequila isn't your thing, feel free to use rum/vodka/pisco/cachaca/aguardiente/grappa or your choice of alcohol